File:Immortal Cave anime.png

Summary
The "Immortal Cave" as it appears in Episode 18 of the Kishin Douji Zenki Anime.

It might be, that the "Underground Tunnel" in Den Ei Rai Bu was based on this anime location, as they look very similar.

The screenshot was made by Semerone and uploaded by

All credit for this image goes to Kikuhide Tani, Yoshihiro Kuroiwa, Studio Deen, Kitty Films and TV Tokyo.